Use the Commons Digester framework to process data analysis in the Java class library
Use the Commons Digester framework to process data analysis in the Java class library
Summary:
In the Java library, data analysis of various formats often needs to be processed.Commons Digest is a powerful framework that can easily process analysis of data formats such as XML and CSV.This article will introduce how to use the Commons Digester to implement data analysis and provide relevant Java code examples.
1 Introduction
Commons Digester is an event -based Java XML parser.It analyzes the XML document as a Java object by configuration rules, thereby simplifying the process of data analysis.In addition to XML parsing, Commons Digerster can also process other format data, such as CSV, JSON, etc.
2. Installation and configuration
First of all, we need to add Commons Digerster to the project.It can be achieved by adding the following dependencies to the POM.XML file:
<dependency>
<groupId>commons-digester</groupId>
<artifactId>commons-digester</artifactId>
<version>3.3</version>
</dependency>
After the installation is completed, we can start configured the rules of the DIGESTER.
3. Configuration rules
The configuration rules of the DIGESTER include the pattern matching and the definition of the rules.The pattern matching is used to specify the node path to be parsed, the rules define it to specify how to parse the node and how to map the analytic results to the Java object.
Below is a sample xml file:
<employees>
<employee>
<name>John</name>
<age>25</age>
</employee>
<employee>
<name>Jane</name>
<age>30</age>
</employee>
</employees>
Below is a regular configuration example of the rules of the XML file using DIGESTER:
// Create a DIGESTER object
Digester digester = new Digester();
// Set the rules
DIGESTER.ADDOBJECTCREATE ("Employeees/Employee", Employee.class); // Create an Employee object object
DIGESTER.ADDBEANPROPROPRTYSETER ("Employees/Employee/name", "name"); // Set the name property
DIGESTER.ADDDBEANPROPROPRTYSETER ("Employees/Employee/Age", "Age"); // Set the Age property
DIGESTER.ADDSETNEXT ("Employees/Employee", "AddemPloyee"); // Add the analysis results to
// Call the PARSE method for analysis
List<Employee> employees = digester.parse(xmlFile);
Through the above configuration, Digester will create an Employee object based on the rules and set the name and Age property to the corresponding value.Finally, add the analysis results to a list.
4. Other functions
In addition to basic XML analysis, Commons Digest also provides other powerful functions, such as custom rules, error treatment, naming space processing, etc.Developers can use these functions according to specific needs.
in conclusion:
By using the COMMONS DIGESTER framework, we can easily process data analysis in various formats in the Java library.This article introduces the basic usage of Commons Digester and gives relevant Java code examples.It is hoped that this article will help readers when processing data analysis.
Reference materials:
-COMMONS DIGESTER official document: [https://commons.apache.org/digerster/] (https://commons.apache.org/digester/))
-POMMONS DIGESTER GITHUB Warehouse: [https://github.com/apache/commons-digerster] (https://github.com/apache/commons-digerster)